Using ESO's Very Large Telescope (VLT), Tom Seccull, from Queen's University Belfast in the UK, and colleagues found that an unusual object at the Kuiper Belt, a region at the edge of the Solar System and beyond the orbit of planet Neptune, is a carbon-rich asteroid.
2004 EW95
The space rock called 2004 EW95 is the first of its kind that researchers found exiled from the inner Solar System.
Researchers said that the asteroid likely formed in the asteroid belt between Jupiter and Mars but was eventually hurled out billions of miles into its new home in the Kuiper Belt.
Scientists have long suspected that many objects in this region originated much closer to Earth but how did they get there?
Ejected Far Into Space
Some theories point to the behavior of gas giants like Saturn and Jupiter during the early stages of the Solar System's formation.
These theories posit that the gas giants did not start their life in a fixed orbit but rather careened through the galaxy accreting materials, bouncing against each other's gravity, and throwing out smaller in their path far into space.
If these theories are correct, some of the asteroids that orbit around Kuiper Belt should be the same carbonaceous asteroids that are commonly found in the asteroid belt between Mars and Jupiter.
Observations of 2004 EW95 revealed the presence of minerals phyllosilicates and ferric oxides.
These minerals suggest that the object formed under conditions similar to those that formed many of the carbonaceous asteroids closer to Earth.
Light reflection data also suggest that the space rock sustained a massive blow that caused it to heat up significantly.
Renegade Gas Giants
Researchers said that the asteroid's characteristics are consistent with the idea that it may have formed near Jupiter along with other carbonaceous asteroids, and that it was thrown into the Kuiper Belt by migrating planets.
If the asteroid is indeed a carbon-rich exile that was kicked out of its original home by a young gas giant, it offers confirmation to theories that gas giants partied up in the early days of the solar system and ejected rocky orbits into far-away orbits.
"The discovery of a carbonaceous asteroid in the Kuiper Belt is a key verification of one of the fundamental predictions of dynamical models of the early Solar System," said ESO astronomer Olivier Hainaut.
The findings were published in The Astrophysical Journal Letters.
